This application relates to chemically modified polyacrylonitrile (PAN) obtained by reaction of PAN with HX, to a corresponding method for modifying PAN and to the use of the modified PAN as an immobilization substrate, inter alia.
Polyacrylonitrile has been modified in various ways in the past. For example, A. L. Endrey, J. Poly. Sci., Poly. Chem. Ed. 20 2105 (1982) discusses the conversion cf polyacrylonitrile to a black form having the suggested structure: ##STR1## In addition to being black, it is hygroscopic, insoluble in all solvents, and has no nitrile groups.
M. Okamoto, T. Ogura, R. Ashihawa, and O. Ishizuka, Chem. Soc., Japan 566-570 (1983) found that polyacrylonitrile reacts very little with HCl below 220.degree. C. Above this temperature, the nitrile groups are polymerized giving: ##STR2## in which all nitrile groups have been polymerized and only a single Cl group is contained. The heat-treated polyacrylonitrile has been used to immobilize enzymes.
S. O. Bachurin et al, Doklady Ahademii Nauk, USSR 253 370-372 (1980) (English Translation) oxidized heat-treated polyacrylonitrile with HNO.sub.3 and then absorbed hydrogenase on it. The binding is reversible.
K. Matsumoto et al, U.S. Pat. No. 4,486,549 (Dec. 4, 1984) (to Toyo Jozo Co.) reduced polyacrylonitrile with LiAlH.sub.4 to produce some amine groups. This was used as a binding support for proteins.
Polyacrylonitrile has also been derivatized with an alcohol under the influence of HCl. The imidioester is then converted to an amidine: ##STR3##
T. Handa, A. Hirose, S. Yoshida, H. Tsushia, Biotech. and Bioeng. 24 1639-1652 (1982) used the product to mobilize glucoamylase. A. Biondi, M. Pace, O. Brenna, and P. G. Pielta, Biochem. 61 171-174 (1976) coupled oxidase, glucose oxidase, and lactate dehydrogenase to alcoholated polyacrylonitrile.
In addition, U.S. Pat. No. 2,810,726 discloses the reaction of dinitriles, such as succinonitrile or glutaronitrile, with HX to produce compounds of the formula: ##STR4## wherein X is Br or I and n is 2 or 3.